TinyDB is a query
processing system for extracting information from a network of TinyOS
sensors.

Unlike existing solutions for data
processing in TinyOS, TinyDB does not require you to write embedded C
code for sensors. Instead, TinyDB provides a simple, SQL-like interface
to specify the data you want to extract, along with additional
parameters, like the rate at which data should be refreshed -- much as
you would pose queries against a traditional database.

Given a query specifying your data
interests, TinyDB collects that data from motes in the environment,
filters it, aggregates it together, and routes it out to a PC. TinyDB
does this via power-efficient in-network processing algorithms.